A wide range of adhesive articles are used in medical applications. These adhesive articles include gels used to attach electrodes and other sensing devices to the skin of a patient, a wide range of tapes to attach medical devices to a patient, and adhesive dressings used to cover and protect wounds.
Many of the adhesive articles use pressure sensitive adhesives. Pressure sensitive adhesives are well known to one of ordinary skill in the art to possess certain properties at room temperature including the following: (1) aggressive and permanent tack, (2) adherence with no more than finger pressure, (3) sufficient ability to hold onto an adherend, and (4) sufficient cohesive strength to be removed cleanly from the adherend. Materials that have been found to function well as pressure sensitive adhesives are polymers designed and formulated to exhibit the requisite viscoelastic properties resulting in a desired balance of tack, peel adhesion, and shear strength. The most commonly used polymers for preparation of pressure sensitive adhesives are natural rubber, synthetic rubbers (e.g., styrene/butadiene copolymers (SBR) and styrene/isoprene/styrene (SIS) block copolymers), various (meth)acrylate (e.g., acrylate and methacrylate) copolymers, and silicones.
One problem with using adhesive articles for medical applications is that the removal of adhesive article can cause trauma to the skin. This is particularly troublesome in patients with sensitive skin, such as infants and the elderly, and can become severe with chronic patients where adhesive articles are repeatedly attached and removed over a long term period.
Various attempts have been made to mitigate this problem with adhesive articles. In particular, health care professionals utilize removal techniques to mitigate skin trauma. One way to mitigate trauma to the skin is to remove the adhesive article using a slow peel at a high angle to avoid stretching the skin. Another way to mitigate trauma, when the adhesive article is stretchable, is to pull straight out (as close to a 0° angle as possible) to induce stretch releasing of the adhesive layer from the skin. Also, manufactures of adhesive articles have developed articles that mitigate skin trauma. So called “gentle-to-skin adhesives” have been developed that provide sufficient adhesion to skin to adhere the adhesive article to the skin, but do not strip off skin cells significantly when removed.
A variety of gentle-to-skin articles and dressings that use gentle-to-skin adhesives have been described. A gentle-to-skin adhesive is described in US Patent Publication No. 2011/0212325 (Determan et al.) which describes an electron beam and gamma radiation crosslinked silicone gel adhesive that may use either nonfunctional or functional poly diorganosiloxanes. In the European Patent No. EP 2,001,424 (Cotton), adhesive laminate dressings are described that include a hydrophobic gel adhesive useful as the skin contact layer, and also contain a structural layer having the gel adhesive on one side and a pressure sensitive adhesive on the other side. Also, U.S. Pat. No. 5,891,076 (Fabo) describes a hypertrophic scar dressing that includes silicone-gel on that side of the dressing which lies against the user's skin and a flexible carrier sheet embodied within the silicone-gel such that the gel forms continuous layers on both sides of the carrier, and US Patent Publication No. 2010/0331785 (Fabo et al.) describes a dressing that includes a liquid impermeable film layer coated with a skin friendly adhesive on the side intended to adhere to the skin.
Additionally devices for affixing medical articles have been described. In US Patent Publication No. 2010/0307513 (Svensby et al.) a component for affixing an article of a medical-technical nature to skin is described that includes a layer of support material coated on one side (the side to be adhered to skin) with a layer of skin-friendly, soft pressure sensitive adhesive, and a fastening area on the top face of the support material layer. PCT Publication No. WO 2012/033456 describes a fixation device for retaining a skin penetrating medical device on the skin of a patient. The fixation device includes a retaining component that includes a support layer having an adhesive coating and a landing zone component adapted to be adhesively attached to the skin around the point of penetration.